The present invention relates generally to materials handling, and in particular, to an apparatus for orienting generally cylindrical articles in specified fashion, for subsequent printing with desired indicia.
While applicable to the handling of a variety of different articles, the present subject matter is described with particular reference to the handling of shapes which are commonly used by the pharmaceutical industry in packaging various medicinal compounds, or by the food industry in packaging various candies and the like. In their preparation, it is the usual practice to imprint certain indicia on the surfaces of such articles, including, for example, the name of the manufacturer or a tradename identifying the article, or to provide other information which may be required by the Food and Drug Administration or by other Governmental agencies.
One technique which is often used to imprint such indicia is the spin printing technique. In such case, the preferred practice is to orient the article, prior to imprinting, so that the indicia are applied at the same desired location on each article imprinted. Thus, it is important that such articles be uniformly supplied to the spin printing device in correct orientation.
Such spin printing techniques have been found to be particularly useful in applying indicia to the telescoping two-part capsules which are commonly used by the pharmaceutical industry to package various medicinal compounds. To this end, a variety of methods and devices have been suggested in the past for orienting such capsules so as to promote a spin printing operation, several of which have been adopted for use by the pharmaceutical industry. Examples of a general class of apparatus which has found broad acceptance in the pharmaceutical industry may be had with reference to U.S. Pat. Nos. 4,394,933; 4,369,702; and 4,266,478. Reference is also made to the subject matter of International Publications No. WO 82/03843 and No. WO 82/03842 and the devices which they describe. In each case, there is generally described a capsule orienting apparatus wherein capsules generally comprising a cap portion overfitting a body portion are placed within a feed hopper in random orientation for sequential delivery to a first, rectifying drum followed by a second, transfer drum, which combine to place (rectify) the capsules in a desired orientation for eventual transfer to a conveying mechanism which is capable of drawing the oriented capsules past a spin printing device.
In connection with those patents listed above, spin printing of the oriented capsules is accomplished by delivering the oriented capsules from the transfer drum to a third rotating drum which is provided with a series of carriers disposed in its periphery so as to enable each carrier to rotate about its axis as the drum rotates about its access. A cam and follower arrangement is then used to rotate each carrier from a first position in which each carrier is aligned so as to receive an oriented capsule from the transfer drum (a longitudinal position) to a second position which is more appropriate for spin printing (a transverse position). Thus, the printing operation becomes dependent upon movable carriers which are subject to wear, particularly at the cam and follower interface. It was therefore deemed desirable to eliminate this potential for wear in order to reduce servicing intervals for the apparatus.
One such attempt in eliminating the need for rotating carrier elements may be had with reference to U.S. Pat. Nos. 4,413,566 and 4,266,477. As previously, the apparatus disclosed incorporates a pair of drums which are useful in placing a quantity of capsules in a specified orientation, in this case such that the body portion of the capsule precedes the cap portion upon its discharge from the transfer drum. The oriented capsules are then transferred to a conveyor comprised of a series of carriers having sloped surface portions which are useful in directing the capsules toward capsule receiving pockets which are properly oriented for subsequent spin printing operations to take place. To assist in this process, this turning of capsules is initiated by a configured shoe associated with the back guide which cooperates with the transfer drum to deliver the capsules to the conveyor. While such structure has served to rotate received capsules through an appropriate angle without necessitating the use of a rotating carrier construction, this technique has not proven to provide the degree of reliability which is desired in connection with the handling of such articles on a mass production basis. Thus, the need remained to develop a reliable means for rotating capsules as previously described without necessitating the use of a rotating carrier construction.